How to Calculate pH

What is pH?

pH is the negative base-10 logarithm of hydrogen ion concentration [H⁺]. This calculator converts between [H⁺] (mol/L) and pH — the fundamental measure of acidity.

Formula

pH = −log₁₀[H⁺] | [H⁺] = 10^(−pH)

[H⁺]: Hydrogen ion concentration (mol/L)
pH: Power of hydrogen (dimensionless)
pOH: Power of hydroxide (dimensionless)

Step-by-Step Guide

1pH = −log₁₀([H⁺])
2[H⁺] = 10^(−pH)
3pH < 7: acidic; pH 7: neutral; pH > 7: alkaline
4Each pH unit = 10× change in [H⁺]

Worked Examples

Input

[H⁺] = 0.001 mol/L

Result

pH = −log(0.001) = 3 (acidic)

Input

pH = 11

Result

[H⁺] = 10⁻¹¹ mol/L (strongly basic)

Frequently Asked Questions

What is Ph Calculation?

pH is the negative base-10 logarithm of hydrogen ion concentration [H⁺]. This calculator converts between [H⁺] (mol/L) and pH — the fundamental measure of acidity

How accurate is the Ph Calculation calculator?

The calculator uses the standard published formula for ph calculation. Results are accurate to the precision of the inputs you provide. For financial, medical, or legal decisions, always verify with a qualified professional.

What units does the Ph Calculation calculator use?

This calculator works with inches. You can enter values in the units shown — the calculator handles all conversions internally.

What formula does the Ph Calculation calculator use?

The core formula is: pH = −log₁₀([H⁺]). Each step in the calculation is shown so you can verify the result manually.

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